Field of the Invention
The embodiments herein are generally directed to automating the timing of output from production source devices that use an internet protocol (IP) network to communicate with a system reference point in a media production studio.
Description of the Related Art
Media production studios (e.g., television studios or film studios) typically include a video production system with several different source devices, like cameras, video players, graphic devices, etc., and a reference point device, like a video switcher. In these production studios, each source device that is used in the production must have its video output timed to arrive at the video switcher so that the video signals (frames, lines and pixels) of each device are aligned to each other and to the switcher's internal clock. In traditional systems, each source device is directly connected to the reference device, for example through a coaxial cable. The output timing of the signal from the source devices must be adjusted to compensate for latency in signal transmission due to factors like cable lengths between the source device and the video switcher, drift in the stability of the internal synchronization of devices to a reference clock, and the varying assignment of production resources to various studios and productions.
Traditionally, this adjustment was done manually. A technician would manually adjust the phase and delay of the video signal leaving each source device, based on verbal instructions from another technician watching the video signals on a video scope. More recently, many systems include a small auto-timing window, where as long as the source signals are within a pre-defined time period (for example, within +/−½ of a line), the reference device can align the signals automatically. With both approaches, aligning the video signals is time and labor intensive, and must be repeated as part of routine maintenance procedures, each time the configuration of the media production studio is changed, and when devices are added to the media production studio.